Cleaning products and fabric care products are available in various forms, such as granular compositions, liquid compositions and tablets. It is also known to put cleaning products and fabric care products in unit dose sachets, which can be water-soluble or water-permeable, to release the product when added to water. Known sachets, for example laundry sachets, may have two compartments, which each comprise different ingredients, typically ingredients which are not compatible with one another. These compartments are typically attached to another and simultaneously release the products.
WO02/08380 discloses an article comprising a first pouch made of a water-reactive material which comprises in its interior:                a) a first solid or liquid composition; and        b) a second pouch made of a water-reactive material comprising in its interior a second solid or liquid composition.        
In one embodiment the first pouch contains therein a first composition and a second pouch contains therein a second composition. The first pouch is made of a material which releases the first composition significantly earlier than the second pouch releases the second composition. Preferably, the first composition is a builder composition, while the second composition is a fabric care composition, fabric cleaning composition, or hard surface cleaning composition. Such an embodiment preferably employs a first pouch which quickly dissolves and/or ruptures to release the first composition, and a second pouch which dissolves and/or ruptures more slowly to release the second composition.
This arrangement provides especially useful benefits, such as allowing sequential water softening and subsequent cleaning.
The pouches are made from a water-reactive material, i.e. material which either dissolves, ruptures, disperses or disintegrates (or mixtures thereof) upon contact with water, releasing thereby the composition. Preferably, the material is water-soluble.
The first pouch will react in water to release its contents before the second pouch, due to the nature of the construction of the article. To further enhance this sequential release, the first pouch may be more water-soluble than the second pouch. This can for example be achieved by using different type of material for the first pouch than for the second pouch; for example, the first pouch is made of a material having a different type of polymer, a different plasticiser, different levels components in the material, different coating of the film material, different thickness of the film material.
One of the problems associated with such articles is that it is difficult to obtain release of the compositions precisely at pre-determined times.